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1.
Understanding what determines the geographic spread of innovations can help guide the funding and implementation of research and extension programs. Our approach uses household survey data as model parameters, to simulate behavior across the entire surveyed population and avoid the aggregation bias associated with representative‐farm models. Such a “heterogeneous agent” approach allows us to infer the distribution of a technology's impacts across one set of households, and predict the potential for spreading to another set that shares similar characteristics with respect to natural resource endowments and farming systems. We apply the technique to new cassava varieties in West Africa, finding a strongly poverty‐alleviating impact, with substantial spillover potential from Nigeria to neighboring countries.  相似文献   

2.
Watershed conservation is widely recognized as a major strategy for rural development throughout the developing world. In India, the apparent success of participatory approaches to watershed development resulted in a decentralization of project planning, implementation, and management to local communities at the village scale. We explore the effectiveness of this so‐called community‐based approach in achieving sustainable soil and water conservation in four semi‐arid regions in India, and analyze what factors explain project success. We confirm the result of earlier studies that participatory approaches are more effective in establishing soil and water conservation in the short run. However, our main result is that investments in community organization fail to ensure household commitment to maintenance in the longer term. Without better returns to investment in soil and water conservation and without local institutions to coordinate investment in the long run, the sustainability of participatory watershed management is seriously threatened.  相似文献   

3.
Supermarkets, wholesalers, and tomato growers in Guatemala   总被引:3,自引:0,他引:3  
The article shows the asset‐related determinants and the impacts of the participation of small farmers in supermarkets versus traditional market channels in Guatemala. Compared to farmers selling only to the traditional market channels, farmers selling to supermarket channels are larger (but are in the upper tier of the “small farmer” category), have more capital, and are much more specialized in commercial horticulture in general and in tomatoes in particular. While they have higher yields, they also have higher input use, including use of chemicals. In fact, they severely overuse pesticides and fungicides. Moreover, these greater input expenditures mean that their profit rates are roughly similar to those of farmers in the traditional market channel. Supermarket‐channel farmers prefer the more demanding wholesale‐supermarket channel because it offers lower risks and lower transaction costs to market, a variety of quality grades of tomatoes, all year long. In turn, the supermarkets, who do not buy direct but rather source from a few specialized‐dedicated wholesalers, rely on this year‐round supply, lower transaction costs, and consistency of quality.  相似文献   

4.
Sustainable agricultural intensification is an urgent challenge for Sub-Saharan Africa. One potential solution is to rely on local farmers' knowledge for improved management of diverse on-farm resources and integration among various farm enterprises. In this article, we analyze the farm-level impact of one recent example, namely the integrated aquaculture–agriculture (IAA) technologies that have been developed and disseminated in a participatory manner in Malawi. Based on a 2004 survey of 315 respondents (166 adopters and 149 nonadopters), we test the hypothesis that adoption of IAA is associated with improved farm productivity and more efficient use of resources. Estimating a technical inefficiency function shows that IAA farms were significantly more efficient compared to nonadopters. IAA farms also had higher total factor productivity, higher farm income per hectare, and higher returns to family labor.  相似文献   

5.
This article compares and analyzes land use and income diversification among two distinct groups of farmers in the Brazilian Amazon: recent colonists in Ouro Preto do Oeste, Rondônia, and traditional long‐term residents along the Tapajós River, Pará. We investigate the hypothesis that farmers who diversify their cash income sources clear less forest on an annual basis, and we compare these livelihood choices across colonist and traditional populations. In particular, we develop a conceptual model based on the household production framework and use econometric models to identify determinants of diversification and forest clearing. We find that diversification of agricultural cash crops is negatively correlated with forest clearing by colonists, providing limited evidence for the hypothesis. Other significant covariates of diversification and forest clearing include cash income levels, stage in family life cycle, cattle ownership, and chemical inputs. Differences in these variables, and differences in household response to these variables, explain variation in diversification and forest clearing across the two populations.  相似文献   

6.
The article analyzes how controlling for differences in land types (defined by position on a low‐scale toposequence) affects estimates of farm technical efficiency for rice farms in eastern India. Contrasting previous research, we find that farms are considerably more technically efficient when efficiency estimates are carried out at the plot level and control for plot characteristics rather than at the farm level without such controls. Estimates show farms cultivating modern varieties are technically efficient and plots planted with traditional varieties on less productive lands (upland and midupland) operate close to the production frontier. Significant technical inefficiency is found on more productive lands (medium and lowland plots) planted with traditional rice varieties. The finding that these smallholder rain‐fed rice farms are efficient cultivators on some plots contrasts with previous findings of farm‐level inefficiency (i.e., rejects overarching explanations linked to farm operator ignorance or lack of motivation) and suggests more complex explanations are required to address the inefficiency that is present.  相似文献   

7.
Based on a random sample of 240 farm households in Chiang Mai province, Thailand, this study shows that—contrary to widespread belief—Karen farm households are well-integrated into markets. Average levels of market integration are 31% for gross farm output, 35% for variable inputs, 49% for food consumption, and 80% for net family income. By estimating a two-stage least squares (2SLS) regression model, this study finds that integration into output markets is positively associated with a diversification of land use away from rice monoculture, more intense contact with nearby urban centers, and a greater number of roads connecting the village to the outside world. Controlling for these factors, the distance to urban centers does not impede market integration; distant villages are equally well integrated into output markets. The study further finds that integration into output markets improves farm productivity and net per capita income. Concerns about market integration are discussed. Results have implications for Thai policy makers who have recently placed increasing emphasis on the concept of "sufficiency economy" in order to promote the well-being of rural people.  相似文献   

8.
Supply response in Ethiopia: accounting for technical inefficiency   总被引:1,自引:0,他引:1  
Few empirical studies of supply response using the profit function have accounted for technical inefficiency. Using farm‐level panel data from Ethiopia, this study examines the effect of incorporating technical inefficiency in estimating the supply response of peasant farmers. Two systems of output supply and input demand equations are estimated and compared: the conventional model in which technical efficiency is assumed and another in which technical inefficiency is explicitly incorporated. The model with technical inefficiency is preferred on grounds of theoretical consistency and improved estimates, although model comparison tests are not conclusive. Incorporation of inefficiency generally increases the magnitudes and the statistical significance of own price elasticities, substantially so in the case of fertilizer and fertilizer‐intensive crops, and alters the priority attached to nonprice factors. An important result is that only the specification with inefficiency reveals a significant effect of access to extension services on output. Only this specification finds that output increases with household size, which one expects as the farms in the sample are largely subsistence and producing for own consumption. Furthermore, the results demonstrate that farmers' response to incentives is considerably restricted by inefficiency, suggesting that the traditional model would overstate response by excluding the efficiency variable.  相似文献   

9.
In Vietnam, a quasi-private property regime has been established in 1993 with the issuance of exchangeable and mortgageable long-term land use right certificates. Using primary qualitative and quantitative data collected in a mountainous district of Northern Vietnam, this paper investigates the role of the land policy in the adoption of soil conservation technologies by farmers. This issue is of crucial importance in the region where population growth and growing market demands have induced farmers to intensify agricultural production. While poverty has been reduced, environmental problems such as soil erosion, landslides, and declining soil fertility have become more severe over the past years. Our findings suggest that despite farmers’ awareness of erosion, soil conservation technologies are perceived as being economically unattractive; therefore, most upland farmers continue to practice the prevailing erosion-prone cultivation system. Focusing on agroforestry as one major soil conservation option, we estimate household and plot-level econometric models to empirically assess the determinants of adoption. We find that the possession of a formal land title positively influences adoption, but that the threat of land reallocations in villages discourages adoption by creating uncertainty and tenure insecurity. The analyses reveal that these two effects interact with each other but are of small magnitude. We conclude that the issuance of land titles is a necessary but not sufficient prerequisite to encouraging the adoption of soil conservation practices. However, current practices remain economically unattractive to farmers. This deficiency needs to be addressed by interdisciplinary research and complemented by strong efforts by local authorities to promote sustainable land use.  相似文献   

10.
11.
Although adoption rates of genetically modified crops have been staggering in some countries, there is still comparatively little evidence about biotechnology impacts under diverse agroecological and institutional conditions. These knowledge gaps lead to an overly precautious attitude among policy makers and the public. This article analyzes the effects of Roundup Ready (RR) soybeans in Argentina, the country with the second biggest transgenic area worldwide. Based on recent survey data, it is shown that the technology increases total factor productivity by 10% on average, with cost savings being somewhat more pronounced for smaller than for larger farms. The reduction in use of toxic herbicides and of tillage operations entails positive environmental repercussions. Aggregate welfare effects are computed over the 1996–2001 period with a three-region, partial equilibrium model, comprising Argentina, the United States, and the rest of the world. In 2001, RR soybeans created more than US$1.2 billion of economic surplus at the global level. The largest share went to consumers (53%), followed by seed and biotechnology firms (34%), and agricultural producers (13%). Due to comparatively weak intellectual property protection, and thus only small technology mark-ups in seed prices and widespread adoption, Argentine soybean growers receive 90% of the benefits in that country. This demonstrates that farmers in developing countries can gain considerably when they obtain access to suitable foreign innovations through technology spill-overs.  相似文献   

12.
This study employs the propensity score matching model to examine the impact of the adoption of water conservation and intensification technologies on farm output and income among small-scale lowland rice farmers in the Northern Region of Ghana. The matching was conducted based on the Mahalanobis distance combined with the propensity score. Balancing tests by checking the mean standardized absolute bias in the matched sample were conducted as well as a sensitivity analysis was conducted to check for hidden bias due to unobservable selection. The empirical results show a positive and significant impact of the adoption of bunds technology on input demand as well as a positive but insignificant impact on output supply and net returns. Adopters of the dibbling technology were found to have higher output supply, whereas no statistically significant difference was found between the incomes of adopters and nonadopters of dibbling seed method. The results, however, reveal a positive and significant effect on output and net returns when the dibbling method is combined with intensified weeding. The estimates were found to be relatively insensitive to hidden bias.  相似文献   

13.
This paper presents a bio‐economic model of Andit Tid, a severely degraded crop‐livestock farming system with high population density and good market access in the highlands of Ethiopia. Land degradation, population growth, stagnant technology, and drought threaten food security in the area. Drought or weather risk appears to have increased in recent years. The bio‐economic model is used to analyse the combined effects of land degradation, population growth, market imperfections and increased risk of drought on household production, welfare and food security. We find that the indirect effects of drought on household welfare through the impact on crop and livestock prices are larger than the direct production effects of drought. Provision and adoption of credit for fertiliser, although risky in itself, may lead to increased grain production and improved household welfare and food security. Provision of credit may have a negative effect on conservation incentives but this effect may be mitigated by linking a conservation requirement to the provision of credit for fertiliser.  相似文献   

14.
This article presents multi-output, multi-input total factor productivity (TFP) growth rates in agriculture for 88 countries over the 1970–2001 period, estimated with both stochastic frontier analysis (SFA) and the more commonly employed data envelopment analysis (DEA). We find results with SFA to be more plausible than with DEA, and use them to analyze trends across countries and the determinants of TFP growth in developing countries. The central finding is that policy and institutional variables, including public agricultural expenditure and proagricultural price policy reforms, are significant correlates of TFP growth. The most significant geographic correlate of TFP growth is distance to the nearest OECD country.  相似文献   

15.
We tested a theoretical model with the Marshallian inefficiency (H1) and threat of eviction (H2) hypotheses having opposite effects on land productivity on sharecropped plots. The model also assumes that kinship contracts may eliminate or reduce the Marshallian inefficiency (H3) and threat of eviction (H4) effects on land productivity. Our empirical findings were consistent with H2 and H4 being true. We found higher land productivity on sharecropped plots than on share tenants' own plots and higher land productivity on sharecropped plots of nonkin than of kin tenants. The nature of the data allowed controlling for unobservable household characteristics through household fixed effects and for observable plot characteristics. Analyses with and without plot characteristics revealed that these findings were stronger with plot characteristics than without them. Based on the plausible assumption that observable plot characteristics are positively correlated with unobservable plot characteristics this strengthens our conclusion. The results are also supported by first-order stochastic dominance analysis. Sharecropped plots' output value distribution unambiguously dominated the output value distribution from share tenants' own plots. Nonkin sharecropped plots' output value distribution also first-order stochastically dominated the output value distribution from kin sharecrop plots.  相似文献   

16.
Policy makers and interest groups have many questions about the use of improved technologies in developing country agriculture. These include the roles of policies, institutions, and infrastructure in the adoption of improved technologies and their impact on productivity and welfare. Most micro‐level adoption studies, however, cannot address these important policy issues. Drawing on an extensive review of the literature on the adoption of agricultural technologies, this article suggests alternative approaches for designing technology adoption studies to make them useful for policy makers. It explores the generic limitations of cross‐sectional adoption studies carried out in small numbers of communities and discusses some problems faced in conducting such studies. Recommendations include the use of sampling approaches that allow data from microstudies to be generalized to higher levels of aggregation, adherence to clearly defined terms that are standardized across studies, and careful examination of the assumptions that often underlie such studies.  相似文献   

17.
The dramatic increase in the price of rice and other commodities over the past year has generated new interest in how these markets work and how they can be improved. This article uses an exceptionally rich data set to test the extent to which markets in Madagascar are integrated across space at different scales of analysis and to explain some of the factors that limit spatial arbitrage and price equalization within a single country. We use rice price data across four quarters of 2000–2001 along with data on transportation costs and infrastructure availability for nearly 1,400 communes in Madagascar to examine the extent of market integration at three different spatial scales—subregional, regional, and national—and to determine whether non-integration is due to high transfer costs or lack of competition. The results indicate that markets are fairly well integrated at the subregional level and that factors such as high crime rates, remoteness, and lack of information are among the factors limiting competition.  相似文献   

18.
A prospective evaluation of biotechnology in semi-subsistence agriculture   总被引:1,自引:0,他引:1  
  相似文献   

19.
This paper seeks to quantify the acreage responses of wheat, cotton, sugarcane and rice in Pakistan using co‐integration techniques and impulse response analysis. Results indicate that acreages of wheat and basmati rice do not respond significantly to shocks in own‐price while cotton, sugarcane and high yielding variety (HYV) rice do, and that long‐run equilibrium is re‐established after about 4 years. Irrigated area is an important determinant of acreage.  相似文献   

20.
Notwithstanding the ambiguous research and productivity promoting effects of plant variety protections (PVPs) even in developed countries, many developing countries have adopted PVPs in the past few years, in part to comply with their Trade‐Related Aspects of Intellectual Property Rights (TRIPS) obligations. Seeking and maintaining PVPs reserves options to an expected revenue stream from the future sale of protected varieties, the value of which varies for a host of reasons. In this article we empirically examine the pattern of PVP applications in China since its PVP laws were first introduced in 1997. We place those PVP rights in the context of China's present and likely future seed markets to identify the economic incentives and institutional influences on decisions to develop and apply for varietal rights.  相似文献   

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